<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* 写样式之前必须样式重置 */
        *{
            margin: 0;padding: 0;
        }
    </style>
</head>
<body>
    <h1>h1</h1>
    <input type="text">
    <p>p</p>
    <div>div</div>
    
</body>
</html>